Hydrolyzation of pentosan containing protein materials



E. C. PATTEE Dec. 11, 1951 HYDROLYZATION OF PENTOSAN CONTAINING PROTEIN MATERIALS Filed Sept. 30, 1948 Patented Dec. 11, 1951 .HYDROLYZATION OF PENTO CONTAIN- ING PROTEIN MATERIALS 1 Ellis 0. Pattee, Cincinnati, Ohio, assignor toNational Distillers Products Corp., a corporation of Virginia Application September30, 1948, Serial No. 52,117 2 Claims. (01.260-529') This invention relates to new and useful improvement in the hydrolyzation of pentosan containing protein materials.

In the conventional preparation of amino acids from protein materials, the latter are. subjected to hydrolyzation with a suitable acid, usually an aqueous solution of a strong inorganic acid such as H2804 or H01. If the protein material contains pentosans, furfural is formed as the result of the hydrolyzing digestion of the pentosans.

Gne object of the instant invention essentially comprises a simple and effective procedure for substantially continuously removing furfural in the hydrolyzation of a protein material containing pentosans.

The foregoing and further objects of the invention will be more fully understood from the following description read in conjunction with the drawing representing a diagrammatic illustration of an arrangement permitting the carrying out of the novel method in' accordance with the invention.

As illustrated in the drawing, lrepresents a steam jacket heated digester provided with a pressure cover 5, provided with. pressure gauge 2 communicating with the interior of the digester l. The 'digester is mounted on legs 3 and carries pressure gauge t communicating with thesteam jacket of the digester. Still connection 7- controlled by valve Bis mountedon cover in communication with the interior of digester l. A packed column 9 is secured to still connection I by the flanged portion 9a, and extends upwardly into the neck portion ll carrying at its upper end elbow connection I8. A combination condenser trap and reflux unit Iil is provided, being secured with the substantially horizontally extending upper condenser conduit l2 t the elbow l8. A lower, substantially horizontally extending condenser conduit IZa is connected to conduit l2 by way of the T-connection l9 and elbow [2 respectively. Lower conduit l2a communicates with one end of the U-shaped trap IS, the other end of which is secured to the reflux neck ll mounted on the connection ll. Draw-01f pipe [4, controlled by valve I5, is connected to the lower portion of trap l3. Condenser conduits l2 and Ho are respectively surrounded by the cooling jackets 2i and 2la. The jacket 2la is provided with inlet 22 controlled by valve 23, and jacket 2i is provided with outlet 24. A conduit 25 connects the end portions of jackets 2| and Zia. The reflux condenser is provided with vent 28 mounted on T-connection l9 and controlled by valve 26. Valve 26 may be adjusted to hold the ill , 2 ystem at or about atmosphericpressure. Alternatively, valve 26 may be adjusted so that the vent .2 8 willoperate to hold the system .athi'gher pressures.

In, practical operation, a suitable pentosan containing protein material is placed into the.

digester l, and provided with a hydrolyzing acid such as aqueous sulfuric and/or hydrochloric acid. I prefer toadd to. theprotein material at least one chemical equivalent of HCl for each gram atom of hitrogenand-at leastohe chemical equival'er'it ofH-zSOiiOI each-gramatom of nitro- 7 gen, and preferably notexceeding 1.5 chemical equivaients oi H2804. for each gram atom of, nitrogen present. The inorganic.- ac ds are. pres.-

ent preferably tothe extent obit-25% by weight of the combined weight-ref thewater and inorganic' acid.

,fsuitable .pentosan containing materials are. for instance, so-called .distillers dried grains" derived IIOm the starch fermentation of cereals and freed from oily matter, if necessary, by appropriate solvent extractionsuch as with hexane.

The temperature within the dlgester is prefera'b y maintained substantially between and 0., and the mass is kept well agitated. Valve 8 is open and valve litis adjusted to so control vent 28 that the system is substantially main-k tamed at atmospheric pressure. Eentos'an digestion to iurruial will commence, and water and furfural vapors W111 pass into and through the packed column 9 through elbow connection l8 into the condenser conduit l2. At least partial condensation will take place in condenser conduit l2 and the condensate, together with uncondensed vapors, will pass through T-piece l3 and elbow 2 into the lower condenser conduit lZa. Cooling liquid passes countercurrent-fash-' ion into inlet 22 through the jacket 2m through conduit 25 into jacket 2| and out through outlet 25. The condensate passes into the trap l3 separating into a lower furfural layer and anup'per aqueous layer. The iuriural layer trapped in the, trap It can be continuously Withdrawn through the conduit l4 valved at l5, while the upper aqueous layer will continuously flow back through the reflux neck I I into the column 9 and thus into the digester I, thereby assuring that the concentration of aqueous medium in the digester remains substantially constant.

After the completion of the furfural digestion, valve 8 is closed, and the temperature within digesting kettle l is raised. Pressure is permitted to build up and is maintained for a sufiicient The hydrochloric-sulfuric acid combination treatment has the advantage that most of the hydrochloric acid can be removed by. distillation.

The following example is furnished by way of illustration but not of limitation:

Example A 100 pound charge of distillers dried grains was placed into a digester of the type herein described, and equipped with a column condenser and trap arrangement herein illustrated. The

charge was mixed with a'solution composed of about 17 pounds of 66 B. sulfuric acid, about 144*pounds of 18 B. hydrochloric acid, and 164 pounds of water. The mixture was then heated until refluxing began, with the vent valve adjusted to substantially maintain atmospheric pressure within the system. The temperature in the digester was approximately 110 C. Refluxing was continued for a period of about 3 hours continuously withdrawing furfural from the draw-oil pipe. At the end of this time, about 7 pounds of furfural were collected, the mixture remaining in the digester; The mixture in the digester was then ready for such further use as might be desired, such as, for instance, amino acid hydrolyzation.

The foregoing description is for the purposes of illustration and not of limitation and it is therefore my intention that the invention be limited only by the appended claims or their equivalent wherein I have endeavored to claim broadly all inherent novelty.

I claim:

'1. Improvement in mm of pentosan containing protein materials which comprises subjecting an aqueous mix of a pentosan containing protein material to furfural hydrolyzation within a closedsystem by continuously heating the same in the presence of an inorganic hydrolyzing' acid selected from the group consisting oi. aqueous sulfuric and hydro.-

the amino acid hydrolyzachloric acids to a temperature of about -110' C. and substantially maintaining atmospheric pressure within said system, substantially continuously distilling ofi water-furfural vapors within said system, and substantially continuously condensing said vapors within said system, substantially continuously separating condensed furfural within said system' and returning condensed water to the hydrolyzing mix, and subjecting said mix after completed furfural hydrolyzation to amino acid digestion within said system by increasing the pressure therein and recovering amino acids from the last treated mix.

' 2. Improvement in the amino acid hydrolyzation of pentosan containing protein materials which comprises subjecting an aqueous mix of a pentosan containing protein material to furiural hydrolyzation within a closed system by continuously heating the same in the presence of an inorganic hydrolyzing acid composed of aqueous sulfuric and hydrochloric acids to a temperature of about 100-110 C. and substantially maintaining atmospheric pressure within said system, substantially continuously distilling oif water-furfural vapors within said system, andsubstantially continuously condensing said vapors within said system, substantially continuously separating condensed furfural within said system, and returning condensed water to the hydrolyzing mix, and subjecting said mix after completed furfural hydrolyzation to amino acid digestion within said system by increasing the pressure therein and recovering amino acids from the last treated mix.

ELLIS C. PAT'I'EE.

REFERENCES CITED The following references are of record in the file of this patent:

, UNITED STATES PATENTS Number 

1. IMPROVEMENT IN THE AMINO ACID HYDROLYZATION OF PENTOSAN CONTAINING PROTEIN MATERIALS WHICH COMPRISES SUBJECTING AN AQUEOUS MIX OF A PENTOSAN CONTAINING PROTEIN MATERIAL TO FURFURAL HYDROLYZATION WITHIN A CLOSED SYSTEM BY CONTINUOUSLY HEATING THE SAME IN THE PRESENCE OF AN INORGANIC HYDROLIZING ACID SELECTED FROM THE GROUP CONSISTING OF AQUEOUS SULFURIC AND HYDROCHLORIC ACIDS TO A TEMPERATURE OF ABOUT 100-110* C. AND SUBSTANTIALLY MAINTAINING ATMOSPHERIC PRESSURE WITHIN SAID SYSTEM, SUBSTANTIALLY CONTINUOUSLY DISTILLING OFF WATER-FURFURAL VAPORS WITHIN SAID SYSTEM, AND SUBSTANTIALLY CONTINUOUSLY CONDENSING SAID VAPORS WITHIN SAID SYSTEM SUBSTANTIALLY CONTINUOUSLY SEPARATING CONDENSED FURFURAL WITHIN SAID SYSTEM AND RETURNING CONDENSED WATER TO THE HYDROLYZING MIX, AND SUBJECTING SAID MIX AFTER COMPLETED FURFURAL HYDROLYZATION TO AMINO ACID DIGESTION WITHIN SAID SYSTEM BY INCREASING THE PRESSURE THEREIN AND RECOVERING AMINO ACIDS FROM THE LAST TREATED MIX. 